Heretofore, ball-type valves have been employed in high temperature, medium high pressure processes for isolating blocking solids flow. However, various operational difficulties are associated with such valves including seating of the ball due to differential or thermal expansion differences between the ball and the valve seats. Solids plugging problems due to the restricted throat of the valves had been experienced and is due to change in flow direction through the flow passage of the valves. While the concept of employing water coolant or steam heating by jacketing of the valve body for plug, gate and butterfly valves has been employed for various valves, none of these prior art valves, however, have provided a simple-to-manufacture, economical valve which has special suitability for high temperature fluid solids service.
The various prior art references located relative to the present invention include U.S. Pat. Nos. 1,827,266 (Shipley), 3,574,341 (Fehling), 3,698,422 (Freed et al), 3,701,359 (Worley et al), 3,825,030 (Kalsi), 3,901,269 (Henderson), 3,973,585 (Henderson), 3,974,869 (Abe et al), and 3,985,150 (Kindersley).
Worley et al discloses an internally insulated slide valve for throttling and blocking solids flow at high temperatures and high pressures in a fluid solids transfer line. The Henderson patents disclose a jacket block with a hollow housing of heat conductive material (see FIG. 3) which substantially surrounds the body of the fitting (see FIG. 1). A temperature controlling fluid is circulated through chambers in heat transfer relation to the body of the fitting. The Freed et al patent discloses a plug valve for controlling fluid flow therethrough by rotating the plug valve until a port is aligned with lateral passages. These lateral passages are lined with a corrosion resistant liner. Kalsi discloses a plastic-lined valve with a rotatable central fluid conduit for controlling communication between passages. The plastic lining is injection molded into locking engagement with the valve body. Kindersley discloses a ball valve having a changeable tubular insert (made of abrasion-resistant material) situated in the valve for controlling the rates of flow between inlet and outlet bores. Fluid flow throttling also can be accomplished by turning the valve a limited amount. Fehling discloses refractory lining the valve closure which regulates flow of molten metal, while Shipley discloses a metal lining for cooperation with a valve plug. Abe discloses a plug valve supported and sealed in an elastic plastic bearing member which takes up wear and prevents leakage.